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Julien Mlade Graldine Piorkowski Franck Touret Toscane Fouri JeanSlim Driouich Maxime Cochin Hawa Sophia Bouzidi Bruno Coutard Antoine Nougairde Xavier de Lamballerie 《EMBO reports》2022,23(5)
Engineering recombinant viruses is a pre‐eminent tool for deciphering the biology of emerging viral pathogens such as the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). However, the large size of coronavirus genomes renders the current reverse genetics methods challenging. Here, we describe a simple method based on “infectious subgenomic amplicons” (ISA) technology to generate recombinant infectious coronaviruses with no need for reconstruction of the complete genomic cDNA and apply this method to SARS‐CoV‐2 and also to the feline enteric coronavirus. In both cases we rescue wild‐type viruses with biological characteristics similar to original strains. Specific mutations and fluorescent red reporter genes can be readily incorporated into the SARS‐CoV‐2 genome enabling the generation of a genomic variants and fluorescent reporter strains for in vivo experiments, serological diagnosis, and antiviral assays. The swiftness and simplicity of the ISA method has the potential to facilitate the advance of coronavirus reverse genetics studies, to explore the molecular biological properties of the SARS‐CoV‐2 variants, and to accelerate the development of effective therapeutic reagents. 相似文献
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Boutas Ioannis Kontogeorgi Adamantia Dimitrakakis Constantine Kalantaridou Sophia N. 《Molecular biology reports》2021,48(7):5699-5705
Molecular Biology Reports - Galectin-3 is part of a protein group called lectins and acts as a multifunctional glycoprotein due to its expression location. Galectin-3 is expressed by different... 相似文献
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Saskia von Stillfried Sophia Villwock Roman D. Bülow Sonja Djudjaj Eva M. Buhl Angela Maurer Nadina Ortiz-Brüchle Peter Celec Barbara M. Klinkhammer Dickson W.L. Wong Claudio Cacchi Till Braunschweig Ruth Knüchel-Clarke Edgar Dahl Peter Boor 《Microbial biotechnology》2021,14(4):1627-1641
Virus detection methods are important to cope with the SARS-CoV-2 pandemics. Apart from the lung, SARS-CoV-2 was detected in multiple organs in severe cases. Less is known on organ tropism in patients developing mild or no symptoms, and some of such patients might be missed in symptom-indicated swab testing. Here, we tested and validated several approaches and selected the most reliable RT-PCR protocol for the detection of SARS-CoV-2 RNA in patients’ routine diagnostic formalin-fixed and paraffin-embedded (FFPE) specimens available in pathology, to assess (i) organ tropism in samples from COVID-19-positive patients, (ii) unrecognized cases in selected tissues from negative or not-tested patients during a pandemic peak, and (iii) retrospectively, pre-pandemic lung samples. We identified SARS-CoV-2 RNA in seven samples from confirmed COVID-19 patients, in two gastric biopsies, one small bowel and one colon resection, one lung biopsy, one pleural resection and one pleural effusion specimen, while all other specimens were negative. In the pandemic peak cohort, we identified one previously unrecognized COVID-19 case in tonsillectomy samples. All pre-pandemic lung samples were negative. In conclusion, SARS-CoV-2 RNA detection in FFPE pathology specimens can potentially improve surveillance of COVID-19, allow retrospective studies, and advance our understanding of SARS-CoV-2 organ tropism and effects. 相似文献
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Epameinondas Xanthakis Sophia Magkouta Heleni Loutrari Haralambos Stamatis Charis Roussos 《Biocatalysis and Biotransformation》2013,31(3):170-178
The monoterpene perillyl alcohol (POH), an intermediate in the plant terpenoid biosynthetic pathway, has well-established tumor chemopreventive and chemotherapeutic potential. We have previously shown that the primary hydroxyl group of POH is essential for its antitumor and anti-angiogenic activities. In the current study we present the enzymatic synthesis of two POH derivatives with different polar and hydrophobic characteristics, namely perillyl glucoside and perillyl glucoside fatty ester, through a two-step modification. Initial glucosylation of POH on its active hydroxyl group with D-(+)-glucose and subsequent esterification of the perillyl glucoside product with vinyl laurate were carried out using almond β-glucosidase and lipase B from Candida antarctica, respectively, in a low-water system. Optimization of enzymatic reactions was performed to achieve the highest possible conversion yields. The antitumor cell proliferation activity against mouse Lewis lung carcinoma cells was retained in both derivatives, although the perillyl glucoside ester showed greater inhibition than perillyl glucoside. Our results underline the feasibility of enzymatically producing novel bioactive analogs of phytochemicals displaying useful physicochemical properties. 相似文献
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For over 40 years, acid deposition has been recognized as a serious international environmental problem, but efforts to restore acidified streams and biota have had limited success. The need to better understand the effects of different sources of acidity on streams has become more pressing with the recent increases in surface water organic acids, or ‘brownification,’ associated with climate change and decreased inorganic acid deposition. Here, we carried out a large scale multi‐seasonal investigation in the Adirondacks, one of the most acid‐impacted regions in the United States, to assess how acid stream producers respond to local and watershed influences and whether these influences can be used in acidification remediation. We explored the pathways of wetland control on aluminum chemistry and diatom taxonomic and functional composition. We demonstrate that streams with larger watershed wetlands have higher organic content, lower concentrations of acidic anions, and lower ratios of inorganic to organic monomeric aluminum, all beneficial for diatom biodiversity and guilds producing high biomass. Although brownification has been viewed as a form of pollution, our results indicate that it may be a stimulating force for biofilm producers with potentially positive consequences for higher trophic levels. Our research also reveals that the mechanism of watershed control of local stream diatom biodiversity through wetland export of organic matter is universal in running waters, operating not only in hard streams, as previously reported, but also in acid streams. Our findings that the negative impacts of acid deposition on Adirondack stream chemistry and biota can be mitigated by wetlands have important implications for biodiversity conservation and stream ecosystem management. Future acidification research should focus on the potential for wetlands to improve stream ecosystem health in acid‐impacted regions and their direct use in stream restoration, for example, through stream rechanneling or wetland construction in appropriate hydrologic settings. 相似文献